Thursday, February 24, 2011
The BMW X6 is a mid-size luxury crossover released for sale in the second quarter of 2008 by German automaker BMW. The X6 was marketed as a Sports Activity Coupé (SAC) by BMW. It combines the attributes of an SUV (high ground clearance, all wheel drive and all-weather ability, large wheels and tires) with the stance of a coupé (bold styling, dramatic sloping roof). The concept model debuted at the 2007 Frankfurt Auto Show and the production X6 officially debuted at the 2008 North American International Auto Show in Detroit and Montreal International Auto Show. While slightly longer and wider than the X5, it is significantly lower and seats only four people. It is built in BMW's North American plant in Greer, South Carolina alongside the BMW X5, whose platform it shares. It is dubbed a "Sports Activity Coupé (SAC)" by BMW. A hybrid version, the BMW Concept X6 ActiveHybrid, which will be the first such vehicle from BMW, was also announced. Later, in April 2009, the sporty X6 M version was announced, with a 555 hp (414 kW) 4.4-liter turbocharged V8. Initially, the BMW X6 was available in North America (Now released in the UK) in two variants. Both use twin-turbocharged engines. The top-of-the-line model is the xDrive50i which uses an all-new 4.4-litre twin-turbocharged V8 engine. This all new version of the 550i/650i's engine (N62) is being used with twin turbo technology from the 135i/335i. It produces 408 PS (300 kW; 402 hp) between 5,500 and 6,400 rpm, and 600 N·m (440 lb·ft) of torque over a wide range of between 1,800 and 4,500 rpm. It is the first production turbocharged V8 engine in the world to feature its turbochargers between the 'V' section in the middle of the two banks of cylinders. The exhaust and intake manifolds are in the un-traditional position - exhausts top of the engine and engine intakes directed to the outer sides of the 'V'. The other model is the X6 xDrive35i powered by the N54 3.0-litre twin-turbocharged inline-six gasoline engine, producing 306 PS (225 kW; 302 hp) between 5800 and 6250 rpm, and a peak torque of 400 N·m (300 lb·ft) between 1400 and 5000 rpm. This engine also sees duty in the 1, 3 and 5 Series BMW cars. With high under-pinnings and luxury features from the BMW 6 Series, the BMW X6 seats only four persons in total. The rear seats share a centre console based from the BMW 3 Series Coupe (E92).
The high-performance M derivative, the BMW X6 M, includes a twin scroll twin turbo version of BMW N63 engine with Cylinder-bank Comprehensive Manifold (CCM). Engine is rated 555 PS (408 kW; 547 hp) at 6000 rpm and 680 N·m (500 lb·ft) at 1500-5650 rpm. Other features include 6-speed M Sports Automatic transmission with aluminum pull-style paddles on steering wheel, M Dynamic Mode feature, 10 mm (0.4 in) lower Adaptive Drive suspension, 4-piston fixed calipers with 15.6" rotor at front and single piston floating calipers with 15.2" rotor at rear, 20-inch alloy wheels with 275/40R20 front and 315/35R20 run flat tires, special gills in the front fenders, 20-inch light-alloy wheels. The 2010 BMW X6 M has MSRP of US$89,725. The vehicle was unveiled in 2009 New York Auto Show. The BMW X6 M was seen in the 2009 MotoGP as one of the pace cars. In late 2009, BMW introduced an X6 featuring a version of the Global Hybrid Cooperation hybrid power train, popularly known as the two-mode hybrid system. This car was confirmed as being called the BMW ActiveHybrid X6, and it is the world's most powerful hybrid vehicle; it will not be sold in the UK. The production vehicle was unveiled alongside a 7-series hybrid at the 2009 Frankfurt Auto Show. The ActiveHybrid X6 went on sale in December 2009 in the US market with a base price of US$89,765. The drive system featured in the BMW ActiveHybrid X6 consists of a 300 kW (407 hp) V8 power unit with BMW TwinPower Turbo Technology and two electric engines developing 67 kW (91 hp) and, respectively, 63 kW (86 hp.) Maximum system output is 357 kW (485 hp), peak torque is 780 Newton-meters (575 lb-ft.) BMW ActiveHybrid technology offers the driver three significant options: to drive under electric power alone, to use the power of the combustion engine, or to benefit from the combination of both drive modes for short periods of maximum acceleration, using the 485 maximum. Driving completely free of CO2 in the electric mode is possible up to a speed of 37 mph (60 km/h). The hybrid also employs stop-start technology and other energy saving measures to help improve efficiency. The core-vehicle is however very heavy and the petrol power unit limits the extent to which fuel consumption can be reduced in absolute terms. The Turbo-Diesel models in the X6 range use less fuel, for example.
Two diesel variants have been announced, and are expected to constitute as much as 90% of sales volume in European markets. The models are called the xDrive30d and xDrive 35d, respectively. They are powered by BMW's 3.0-litre turbodiesel engine (in its sequential twin-turbocharged variant for the xDrive35d), and produce 235 PS (173 kW) in the xDrive30d and 286 PS (210 kW) in the xDrive 35d version. The second of these power units will form the basis of BMW's Diesel launch in all 50 states in late-2008. The X6 marks BMW's first use of its new Dynamic Performance Control system, which works in unison with xDrive all-wheel drive (both are standard on the X6). DPC is a drivetrain and chassis control system that works to regulate traction and especially correct over- and understeer by actively spreading out drive forces across the rear axle. Torque is split not only between the front and rear wheels (xDrive) but also from side to side at the rear for improved agility and added stability (through the DPC rear axle). The DPC differential features clutch packs on both output sides that are actuated by an electric motor. The clutch pack activates a planetary gearset which causes one wheel to be overdriven. A conventional control system will use the brakes to reduce the speed of the faster moving wheel (which is the one with less traction)and reduce engine power. This leads to increased brake wear and slower than optimal progress. The DPC system speeds up the slower moving wheel (the one with the most traction) in order to maintain stability when needed. For example; while turning, the outer wheel is overdriven to provide greater acceleration using the traction advantage through the dynamic loading of the outboard wheel in cornering. In an oversteer situation, the inner wheel is overdriven to regain traction balance. BMW X6 M was used in MotoGP 2009 as safety car. The vehicle was unveiled in Losail International Circuit in Qatar.